Hold-down device



Aug. 7,1945 J. H. 'HLBum 2,381,815

HOLD DOWN DEVICE Filed July 8, 1943 INVENTQR. JOHN HENRY FILBURN ATTOIQI EY to the drawing forming in which drawing:

Patented Aug. 7 1945 I UNITED STATES PATENT f OFFICE 2,381,815 noLn-nowN DEVICE John Henry rnbum, Detroit, Mien. Application July 8,1943, Serial No. 493,885 2 Claims. (01. 90-60) This invention relates to machinery and particularly to a hold down device to be used in connection with the vise of a milling machine or the like.

Ithas been the practice heretofore, in setting up work on a millingmachine to use two sets of parallels. One set being used to align the hold used to sup down bars, and theother set being port the work piece.

It is an object, therefore, of the invention to provide a hold down device, which will obviate the necessity of using one set of parallels in setting up the work.

Another object of th invention is the pro-' vision of a device of the chanacter referred to, which may be rested by on the jaws of the vise.

Another object of the invention is theprovision of a device, which is simple in construction, economical to manufacture, and eflicient inuse.

The foregoing objects and other advantages of the invention will appear as the description proceeds, reference being made; from time to time part of this disclosure Fig. 1 is a perspective view of a device embodying my invention.

Fig. 2 is a perspective view of a conventional milling machine vise, with a work piece set up,

utilizing one pair of parallels tosupport the work piece, and another set of parallels for supporting the hold down members in the conventional manner. 1 I

Fig. 3 is a front elevational view of the same milling machine vise as shown in Fig. 2, with a work piece held in position by the applicant's im-' proved hold down device. 4

Fig. 4 is a cross section taken substantially on the line 4-4 of Fig. 1.

Referring now more particularly to the drawing, it will be understood that in the embodiment herein disc'losediFig. 1), my improved hold down device consists of a rest bar. I, and .a pinch bar its own weight directly to accommodate the Allen screws l5, which engage corresponding threaded bores in the pinch bar 8, Y

The pinch bar 8, is also preferably formed of rectangular bar stock of suitable size, which is machined as at 16, to provide a substantially 15 degree angle, and machinedas at IT, to provide a substantially 4 degree angle. When the two bars are assembled as shown in Fig. 1, the de vice is ready for use, as shown in Fig. 3.

In Fig. 2, I illustrate the conventional method of 'settingup a work piece l8, which isfsupported by. the parallels I9, and which is held downby I the hold down members 20, which are in turn, supported by the parallels 2!.

It will be noted in Fig. 3, however, that the workpiece I8 is supported by the parallels l9 and u is held down by the pinch bars 8, of applicants hold down device, without the necessity of the second pair of parallels 2|, as shown in Fig. 2.

When a work piece I 8 is set up as shown in Fig. 3, and before the vise is tightened, applicants hold down members will assume the positions indicated by the dotted lines because of the weight of the rest bars 'I. As the vise is tightened, the inside faces of the jaws 9 will contact the four degree angular faces l1, causing the narrow edges of the pinch bars 8 to contact the 8, which are formed and secured together as hereinafter described.

The rest bar 1, is preferably formed of rectan'gularbar stock of sui'ficient size and weight,

so that it will rest of its own weight (Fi 3) on top of the jaws 9, of the milling machine vise ID, the screw of which is designated by the reference character II. I prefer to machine away a portion of the rest bar I, as at I2, to provide the oif set l3, which is drilled and threaded as at M,

work piece I8 and at the same time will rock upwardly the rest bars 1, as shown in Fig. 3.

It will thus'be seen that I have provided a hold down device which is simple in construction and eificient in use.

'Having described my invention what I claim and desire to secur by Letters Patent is:

1. The combination with a vise having a pair of jaws, of a hold down device comprising a counterweight rest bar adapted to rest of its own weight on the upper surface of eachjaw, each of said rest bars being provided with an 011?- set portion from. which depends an angularpinch bar, said pinch bar having an inclined rear surface arranged t contact the vise jaw and cause the pinch bar to rock downwardly in an inclined position when the vise jaws are closed on a work piece. I

' 2. The combination defined in claim '1, in which the pinch bar has a comparatively thin leading edge which, when the'pinch bar is rocked downpinch bar and a work piece.

' JOHN HENRY FILBURN, 

